Valve for steam-engines.



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Patented Mar. I8, |902.

G. B. SMITH.

VALVE FOR STEAM ENGINES.

` (Application filed June 26, 1901.)

(No Model.)

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N0. 695,89l. Patented Mar. I8, |902.

G. B. SMITH.

VALVE FOR STEAM ENGINES (Application filed. June 26, 1901.)

.JEWMWQL lii-"V T4 ATTEST e? 45- TNS/ENTE? gag @VM No. 695,891. PafentodMar. I8, |902.

G. B. SMITH.

VALVE FOR STEAM ENGINES.

(Application filed June 26, 1901.) Y (No Model.) 3 sheets-*sheet 3.

il'rviTnn STnTns FATnNT OFFICE.

GARY I3. SMITH, OF CLEVELAND, OHIO, ASSIGNOR OF TWO-THIRDS TO J. II.COLVELL AND W. II. ELLIOTT, OF CLEVELAND, OIIIO.

VALVE FOR STEAM-ENGINES.

SPECIFICATION forming part of Letters Patent No. 695,891, dated March18, 1902. Application filed June 26, 1901. Serial No. 66,083. (Nomodel.)

To @ZZ wtont it muy concern:

Be it known that I, GARY B. SMITH, a citi- Zen of the United States,residing at Cleveland, in the county of Cuyahoga and State of Ohio, haveinvented certain new and useful Improvements in Valves forSteam-Engines; and I do declare that the following is a full, clear, andexact description of the invention, which will enable others skilled inthe art to which it appertains to make and use the same.

My invention relates to improvements in valves for steam-engines; andthe improvement consists in the construction and arrangement of partswhich provide for the normal running of the engine, the reversal of thesame, and also the throttling or stopping and starting of the engine,all substantially as hereinafter described, and more particularlypointed out in the claims.

In the accompanying drawings, Figure 1 is a central longitudinal sectionthrough the cylinder and valve-chest with the valve-stem in elevationand showing the piston and valve at the extreme end of a stroke and atthe point of return. Fig. 2 is a cross-section of the valve-chest online A A, Figs. 1 and 3. Fig. 3' is a longitudinal section of thevalve-chest at right angles to Fig. 1 and showing the valve parts in thesame position as in that figure. Fig. 4 is a similar view as Fig. 1, butshowing the piston and valve as it occurs at about their half-stroke andwith the inlet or pressure ports nearly closed. Fig. 5 is a crosssectionon line B B, Fig. 4; and Fig. Gis a central sectional view ofthevalve-chest corresponding to Fig. 3, but with the valve in theposition as shown in Fig. 4. Fig. 7 is a corresponding view to Fig. 1,but with the piston and valve in the opposite position as shown therein.Fig. 8 is a central sectional view of the valve-chest at right angles toFig. 7. Fig. 9 is a perspective view of the valve-sleeve. Fig. 10 is aperspective of the valve-stem. Fig. 11 is a sectional view of the chainconnection at the bottom of the valve sleeve and stem. Fig. 12 is acentral longitudinal section of the cylinder and valve-chest, showingthe valve-stem rotated a quarter-turn and in position to reverse theengine. Fig. 13 is a sectional view at right angles to Fig. 12, showingthe relative position of the parts not seen in that iigure. Fig. 14 is across-section on line C C of Fig. 13. Fig. 15 is a cross-section on lineD D, Fig. 1G, showing the valve rotated to position for throttling theengine. Fig. i6 is a vertical section of the valve-chest on the line ofthe inlet and exhaust ports and also showing the valve in throttlingposition. Fig. 17is a vertical sectionalview of the valvebushing, andFig. 18 is a central longitudinal section of the cylinder andsteam-chest with the valve and its bushing removed.

Again referring to the drawings, 2 represents the cylinder, and 3 thevalve-chest, both of which are formed in a single casting, withconnecting steam-ducts4 and 5 leading to opposite ends of the cylinderand at each side of pistou G. The inlet and exhaust pipes 7 and S,respectively, are located centrally between the ends of valve-chest 3and at right angles to steam-ducts 4 and 5. These pipes open intochannels 9, formed in the sides of Valve-chest 3, and a tubular bushing10 for the valve is driven or fastened within the valve-chest to formthe inner wall of the said ducts and channels. This bushing is providedwith three vertical rows of ports 11, 12, and 13, respectively arrangedequally distant on three sides to correspond with the channels 9 andducts 4 and 5. In casting the valve-chest these ports could be formedtherein and a bushing dispensed with; but I prefer to use a separatebushing for several reasons, one of which is that the ports can be moreaccurately cut and also fitted to the valve before placing the bushingin chest 3.

The valve comprises a valve-stem 14 and a tubular sleeve 15 thereon,both of which reciprocate within the bushing to open and close the portsleading to and from the cylinder. The valve-stem is cylindrical and hasa series of slots 16, 17, 18, and 19, respectively, in its sides to formpassages or ducts for the steam, and they control the ports ofvalve-sleeve 15. Slots 17 and 18 are located between slots 16 and 19 andare of greater width as compared with the end slots. Slots 16 and 19 arecut on both sides of stem 14, with a central vertical dividing-wall,whereas slots 17 and 18 are cut only at one side of stem 14 and at rightangles to the end slots. Valveslceve 15 has an equal number of ports asthe bushing-that is, a vertical row of four ports-on three of its sidesand numbered 20, 21, and 22, respectively, and they are arranged in linewith bushing-ports 11, 12, and 13. The sleeve-ports cont-rol the openingand closing of the bushing-ports, and the reciprocal `movement of sleeve15 is limited and occurs only at the latter half of the stroke of piston6. Valve-stem 14 travels always with the piston the full stroke thereof,but in an opposite direction thereto. l

The mechanism for operating the valve consists of a rack 23, adjustablyscrewed on the upper end of valve-stem 14, which rack is engaged by asegment-gear 24, pivotally mounted within cylinder-head 25. A link 26counects arm 27 of segment-gear 24 with piston 6, and as the pistonreciprocates valve-stem 14 is also reciprocated. After valve-stem 14 hasbeen moved the required distance to change the position of its passagesin relation to the ports in sleeve 15 the sleeve itself is carried alongby means of a connecting-,chain 2S, which bridges the bottom end ofsleeve 15 and is pivotally attached at its outer ends thereto. The innerends of chain 28 are pivoted to ears on adj ustablesslotted arms which-are clamped on bolt 29, which bolt is mount- Said plug is screwed intothe end of stem 14 and lockedv vin any adjusted position by a ed'withina threaded plug 30.

lock-nut 31. Stem 14 and its plug 30 are free to rotate about the bolt,which rotation is utilized to reverse the engine as well as to throttlethe same. Valve-sleeve 15 is splined to bushing 10 at 32, andalthough-.held from rotation thereby provision is made for the slidingor end move- Ament of the sleeve.

Referring to Figs. 1 to 3inclusive, the

valve and its ports are shown in one extreme position-that is, whenpiston 6 is at the bottom of its stroke and on the point of going up. Asthe momentum of the ily-wheel carries the'crank of the engine over thedead-center the piston is carried up and valve-stem 14 is forced down,and the steam is directed from inlet-channel 9 through the lowestbushingport 20 and sleeve-port 22 into and through passage or slot 1,6,The lowest port 22 of sleeve 15;is open to the lowest port 13 of thebushing, and the steam is free to pass from slot 16a to duct 5 and intothe cylinder below the piston. The exhaust-ports are also opened at thesame time ,and the exhaust passes from the cylinder through duct 4, port13"L of bushing 10, port 22:L of sleeve 15,passage18 in stem 14, thenthrough port 21fL of sleeve 15, port;12a of the bushing, and into theexhaust-channel 9 and pipe S. As the piston is forced upward by thedirect action ofthe steam passing through the ports just describedvalve-stem 14 is forced down until inlet-passage 16 passes-by and thestem closes lowerport22 in `the valve-sleeve. hen this occurs, piston 6hastraveled about onehalf itsfstroke or slightly-beyond the positionshown in Fig. 4'and the balance of the stroke is under the expansion ofthe steam now inby means of chain 28, said sleeve having been ypreviously held stationary within'bushing 10 through the frictionalengagement of its packing-rings 35. When both stems 14 and 15 traveldown, all the ports in the sleeve are closed by the stem except theexhaust-ports opposite passage 1S. The object of shifting sleeve 15 isto change the position of its ports in relation to the ports in thebushing, so that when the opposite movement of the piston begins a newset ofports are in open communication to shift the steam-supply andexhaust to opposite sides of the piston. Thus it will be seen byreferring to Figs. 7 and 8 that when this change is edected and thevalve stem and sleeve are at thelimit of their downstroke port 2O:L ofsleeve-15 is opposite the upper inlet-port 11 in bushing 10, and thesteam will pass through passage 19 as soon as the steam moves up andthence through port 22b in sleeve 15, upper port 13 in bushing 10 intoduct 4 and cylinder 2 above the piston. The exhaust is now through duct5, bushingport 13b, sleeve-port'22, stem-passage 17, sleeve-port 2lb,bushing-port 12b, exhaustchannel 9, `and pipe 8. Stem 14 now movesupward and sleeve 15 remains stationary as before or until the slack inchain 28 is taken up, when both stem and sleeve move together to shiftthe ports preparatory to the reverse movement of the piston. v

The foregoing construction provides for the propulsion of piston by bothdirect pressure and expansion of the steam and in addition provides forreversing the engine and the throttling thereof. The reversing isaccomplished by rotating stem 14 Within sleeve 15 a quarter-turn to theleft, as seen in Figs. 12, 13, and 14. Passage 1'7l in stem 14 isthereby brought opposite sleeve-ports 2Oc and 22C, and these portsinstead of becoming the exhaustports become theinlet-ports. Then as thepiston is carried down by the momentum of the ily-wheel it will beagainst the direct pressure of the steam. The movement of said pistonwill be reversed before it reaches the end of its stroke. The valve-stemis immediately rotated to the normal running position and the engine isdriven as before, but with the power-shaft in reverse rotation.

The throttling of the engine or cutting off of the steam is accomplishedby rotating stem 14 a quarter-turn to the right-that is, to the positionshown in Figs. 15 and 16. Here it will be seen that stem 14 completelycloses the intermediate ports leading from inletchannel 9 and alsoprevents the iiow of steam to the cylinder at the end ports and stem-vpassages bythe central vertical dividing-wall between the end slots 1Gand u19 in stem 14v and which directs the steam against the in- IOO nerface of sleeve 15, and thereby confines it entirely to the inlet side ofvalve-chest 3.

The chain connection between the valvestem and its sleeve is of especialadvantage in deadening the sound or knock at the end of each stroke, andbeing adjustable any desired area of port-openings in the sleeve can behad by regulating the distance of travel of the stem within the sleeve.The wear or stretch of chain 2S can also thereby be taken up to readjustthe relative working positions of the stem-passages and sleeve-ports.The slotted arms 44, to which the inner ends of chain 2S are attached,have serrated engaging faces, and after being adjusted laterally toshorten or lengthen the travel of stem 14 are clamped together and heldrigidly upon bolt 29 by a nut 45.

The upper portion of valve-.stem 14 is provided with an angular opening40, within which an angular shaft 41 is seated. Shaft 41 is rotatablymounted in the top of the valve-chamber extension of cylinder-head 27,and a handle 42 at the upper end of said shaft is used to rotate thevalve-stem to either starting, throttling, or reversing position.Valve-stem 14 is free to slide up and down on the angular end of shaft41. Rack 23 is held in adj usted position on the threaded end of stem 14by collar 43, and this adjustment provides for the setting of the stemand sleeve ports at any desired elevation in relation to thebnshingports. the steam can thus be timed to enter and leave thecylinder at any desired period.

Spring-steel packing-rings 35 are used for sleeve 15, and these ringsserve to hold said sleeve tirmlyin position within the bushing 10 duringthe independent or initial movement of stem 14 and until the slack inchains 2S is taken up.

Vith slight modiication the valve might be adapted to operate also as agovernor. In that event governing mechanism would be attached tohandle-shaft 41.

What I claim is- 1. In a steam-engine, the cylinder and piston therein,a valve-chest having inlet and exhaust ports leading to and from saidcylinder, a valve Within the valve-chest comprising a stem havingsteam-passages and a slidable sleeve on said stem provided with ports,means to limit the movement of said stem within said sleeve whereby allthe steam passages and ports therein, except the exhaustports, areclosed at the limit of the movement of said stem within said sleeve, andmeans to reciprocate both stem and sleeve within the valve-chest,substantially as described.

2. In a steam-engine, the combination of a cylinder and piston thereinand avalve-chest having steam ducts and ports leading thereto, areciprocating and rotatable valve within said chest comprising a stemanda sleeve mounted thereon and provided with ports, and means toreciprocate and means to rotate said valve, substantially as described.

The inlet and exhaust of 3. In a steam-engine, the cylinder and pistontherein, the valve-chest and valve therein, steam-ducts betweensaidvalve-chest and cylinder, and inlet and exhaust ports in said chestand valve, said valve comprising a rot-atable and reciprocating stem anda sleeve mounted to slide thereon, whereby reversing and throttling ofthe engine is obtained and means to operate said valve, substantially asdescribed.

4. In a steam-engine, the cylinder and piston therein and a valve-chesthaving inlet and exhaust ports and ducts leading to said cylinder, incombination with a reciprocating valve comprising a stem provided withsteam-passages and a sleeve mounted to slide thereon and provided withports, and an adjustable connect-ion between said stem and sleeve tolimit the sliding movement of said sleeve, and means to operate saidvalve, substantially as described.

5. In a steam-engine, the cylinder and piston therein, the valveechest,inlet and exhanst ports between said cylinder and valvechest, avalvewithin said chest comprising a stem having steam-passages and asleeve mounted to slide on said stem and provided with ports, a chainconnection between said stem and sleeve to limit the movement of saidsleeve upon the stem, and means to operate the valve to open and closethe inlet and exhaust ports, substantially as described.

G. The combination of a rotatable and reciprocal valve for steam-enginescomprising a stem provided with steam-passages, asleeve having steaminlet and exhaust ports in its sides and mounted to slide upon saidstem, means to limit the movement of said sleeve on said stem, and meansto carry both stem and sleeve along together at the limit of themovement of said sleeve on said stem, substantially as described.

7. The combination of a rotatable and reciprocal valve for steam-enginescomprising astem provided with steam-passages, a sleeve provided withsteam inlet and exhaust ports, and mounted to slide upon said stem, aflexible connection between said stem and sleeve whereby the movement ofthe stem is limited before carrying both sleeve and stem along together,and adjusting mechanism attached to said flexible connection wherebysaid stem and sleeve are set to work in different relations to eachother, substantially as described.

8. In a steam-engine, a single castinghaving the piston-cylinder andvalve-chest with their connecting steam inlet and exhaust ports andducts all formed therein, and a separate bushing provided with ports andconstructed to fit and fasten within said valvechest, in combinationwith a reciprocating valve having ports and arranged to slide in saidbushing, substantially as described.

9. In a steam-engine, a single castinghaving the piston-cylinder andvalve-chest with their steam inlet and exhaust ports and pas- ICO sagesall formed therein, and a separate bushing having inlet and exhaustports and constructed to fit-within said valve-chest, in conibinationwith a reciprocating valve arranged to slide in said bushing andcomprising a stem With passages and a sleeve with ports, Said sleevebeing mounted to slide upon said stem, substantially as described.

10. The single casting comprisinga steamengine piston-cylinder and avalve-chest with their inlet and exhaust ports and ducts all formedtherein, in combination with a separate bushing adapted to fit andfasten in said valve-chest, and having inlet and exhaust ports varrangedto openinto said cylinder and valve-chest inlet and exhaust ports andpassages, substantially as described.

1l'. In a steam-engine, the cylinder and piston therein, the valve-chestand its connecting-passages with said cylinder, and inlet and exhaustports and passages to said valvechest, in combination with a valvecomprising a reciprocal stem with passages therein and a sleeve thereonwith ports in its sides, said stem-passages comprising two intermediatepassages arranged at one side of said stem and end passages arranged onboth sides of the stem and at right angles to the interf mediatepassages and having a central vertical dividing-Wall between them thusforming a set of two passages at either end, substantially as described.

other, means to reciprocate said stem and sleeve and spring-rings onsaid sleeve to retard said sleeve du ring part movement of said stem,substantially as described.

13. In a steam-engine, the combination of a piston and a valved stemconnected to operate therewith, said stem having an adjustable rack andsaid piston a link-and-gear segment whereby the movement of said pistonis conveyed to said stem and timed therewith, substantially asdescribed.

14. The combination of a rotatable throttling and reversing valve forsteam-engines comprising a stem having steam-passages, a sleeve havingsteam-ports, a flexible connection between said stem and sleeve andadjustable take-up mechanism for said connection to shorten or lengthenthe movement of said stern in relation to said sleeve, substantially asdescribed.

Witness my hand to Jthe foregoing specification this 11th day of June,1901.

GARY B. SMITH.

Witnesses:

R. B. MOSER, H. E. MUDRA.

